ERAGON, ELDEST, and, this month, BRISINGR

To promote Brisingr, the third book in Christopher Paolini’s Inheritance Cycle (after Eragon and Eldest), Knopf launched an interactive online game in June incorporating various aspects of the series’ storyline. Some 20,000 users signed up to play in the first three weeks. With the hardcover, ebook, and unabridged audio editions (read by Gerard Doyle) of the third installment going on sale Sept. 20, that number has since more than doubled, to 41,000. With momentum like this building, and taking into consideration the immense popularity of the series’ first two titles—in all their formats—here’s a rundown of all that’s available come on-sale day: